The invention relates to a power-operated tightening nut for axially tightening a fastening bolt with an adjustable tightening force.
From the prior art (e.g. product sheet “Mechanical tightening elements” of Enemac GmbH from 2010), such power-operated tightening nuts which are used in tightening technology are known for tightening a fastening bolt axially. For this the power-operated tightening nut is manually screwed onto an external thread of the fastening bolt to be tightened until the power-operated tightening nut rests with its front side contact surface on a corresponding counter-bearing surface. Subsequently, an adjusting screw in the power-operated tightening nut is tightened with a specified torque using a torque wrench, the torque of the adjusting screw determining the tightening force acting on the fastening bolt.
A disadvantage of this known power-operated tightening nut is the fact that the tightening force acting on the fastening bolt can only be derived from the torque which is applied to the adjusting screw. For accurately tightening the fastening bolt with a specified tightening force, a torque wrench is therefore always required for the known power-operated tightening nuts.
Thus the object of the invention is to create an appropriately improved power-operated tightening nut.
This object is achieved by a power-operated tightening nut according to the invention.